;; Constraint definitions for RISC-V target. ;; Copyright (C) 2011-2021 Free Software Foundation, Inc. ;; Contributed by Andrew Waterman (andrew@sifive.com). ;; Based on MIPS target for GNU compiler. ;; ;; This file is part of GCC. ;; ;; GCC is free software; you can redistribute it and/or modify ;; it under the terms of the GNU General Public License as published by ;; the Free Software Foundation; either version 3, or (at your option) ;; any later version. ;; ;; GCC is distributed in the hope that it will be useful, ;; but WITHOUT ANY WARRANTY; without even the implied warranty of ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the ;; GNU General Public License for more details. ;; ;; You should have received a copy of the GNU General Public License ;; along with GCC; see the file COPYING3. If not see ;; http://www.gnu.org/licenses/.
;; Register constraints
(define_register_constraint “f” “TARGET_HARD_FLOAT ? FP_REGS : NO_REGS” “A floating-point register (if available).”)
(define_register_constraint “j” “SIBCALL_REGS” “@internal”)
;; Avoid using register t0 for JALR's argument, because for some ;; microarchitectures that is a return-address stack hint. (define_register_constraint “l” “JALR_REGS” “@internal”)
;; General constraints
(define_constraint “I” “An I-type 12-bit signed immediate.” (and (match_code “const_int”) (match_test “SMALL_OPERAND (ival)”)))
(define_constraint “J” “Integer zero.” (and (match_code “const_int”) (match_test “ival == 0”)))
(define_constraint “K” “A 5-bit unsigned immediate for CSR access instructions.” (and (match_code “const_int”) (match_test “IN_RANGE (ival, 0, 31)”)))
(define_constraint “L” “A U-type 20-bit signed immediate.” (and (match_code “const_int”) (match_test “LUI_OPERAND (ival)”)))
;; Floating-point constant +0.0, used for FCVT-based moves when FMV is ;; not available in RV32. (define_constraint “G” “@internal” (and (match_code “const_double”) (match_test “op == CONST0_RTX (mode)”)))
(define_memory_constraint “A” “An address that is held in a general-purpose register.” (and (match_code “mem”) (match_test “GET_CODE(XEXP(op,0)) == REG”)))
(define_constraint “S” “A constraint that matches an absolute symbolic address.” (match_operand 0 “absolute_symbolic_operand”))
(define_constraint “U” “@internal A PLT-indirect call address.” (match_operand 0 “plt_symbolic_operand”))
(define_constraint “T” “@internal A constant @code{move_operand}.” (and (match_operand 0 “move_operand”) (match_test “CONSTANT_P (op)”)))